Failure to generate function signature

[orenbenkiki]

Sphinx (version 1.5.2) fails to generate function signature in case there are typing problems.

Problem

http://stackoverflow.com/questions/37362351/sphinx-does-not-produce-function-signature contains a good description of the problem (which also happens for me). It seems that if the typing module chokes on some code, sphinx will therefore fail to generate any signature for the affected function. In my specific case (Python 3.6, mypy 0.501), the code actually passes mypy (with the occasional # type: ignore comment), but I still get the WARNING: error while formatting arguments for ...: ... object has no attribute ....

Expected results

Sphinx should generate a function signature regardless of spurious failures of the typing module; the solution suggested in http://stackoverflow.com/questions/37362351/sphinx-does-not-produce-function-signature makes sense.

Reproducible project / your project

I haven't isolated the offending code out of my project - if/when I'll upload the project to Github, I'll add a link to it (this may take a while - my company intends to release it, but for now it is an internal project).

Environment info

• OS: Linux
• Python version: 3.6
• Sphinx version: 1.5.2

[tk0miya]

Thank you for reporting.
LGTM for the patch on SO.

It would be very nice if anybody provides the reproducible example. Then I will patch the code with testcase.

[tk0miya]

Any updates? If none, I can't merge this...

[orenbenkiki]

The solution from stack overflow seems sensible...:

Solution: try-excepting the erroneous code:

So i tried to fix the issue by quick and dirty try-except-clause:

From:

introspected_hints = (typing.get_type_hints(function)
                          if typing and hasattr(function, '__code__')`

to:

try:
   introspected_hints = (typing.get_type_hints(function)
                             if typing and hasattr(function, '__code__')
except AttributeError:
   introspected_hints = {}

Indeed, the quick fix solved both problems: no more Warnings were created and further the
documentation shows the right (!) signature of my functions.

[tk0miya]

No, I'd like to know how to raise the error. I need some example to reproduce the bug before merging it.

[tk0miya]

Any updates? I think this is good fix, so I'd like to merge this. To do that, I need reproducible example.

[tk0miya]

I marked this as "help wanted". Please let me know how to reproduce the problem.

[tk0miya]

Finally I found the reproducible example: #5306!
I made a PR #5309 for this.

[tk0miya]

Fixed.
Thank you for reporting.